Elizabeth Jarvis’ survey was done February 4, 1684.

What’s up with that? The document clearly says February the 4 1683.
OK, let’s deal with this right now. It’s important.
Julian Calendar

The Julian calendar began use in 45 BC. It was used by much of the world. The Julian calendar was much better than the Roman lunar calendar in use earlier.
The old lunar calendar had 10 months, beginning in March. The Julian calendar added January and February.
New Year’s Day
During the Middle Ages, the use of January 1 as the New Year was abolished and the it went back to being celebrated on March 25, coinciding with the Christians’ Annunciation Day.
So March was the first month of the year, and February the last month.

As an example, 24 March 1650 is followed the next day by 25 March 1651. And 31 December 1683 is followed by 1 January 1683.
So you might see the court convening 27 Dec 1636, followed a month later by a court 28 Jan 1636, then the next session 25 Feb 1636 and then 28 Mar 1637.
Gregorian Calendar
In 1582, Pope Gregory mandated that the Roman Catholic world adopt the Gregorian calendar, which was more accurate in calculating leap years. This is the calendar we’re familiar with today. January 1 is the first day of the year.
Protestant countries like England weren’t under the authority of the pope. They continued to use the Julian calendar. But in practice both calendars were in use in England and its colonies after 1582.
The British Empire continued to use March 25 as the first day of the year.

Double Dating

There was confusion. Since both calendars were used, there were two dates for the beginning of the year – the “common year” starting January 1 and the “legal year” beginning March 25.
So you’ll see both years listed for dates in January, February, and March. Elizabeth’s survey date might be written February the 4, 1683/4. February 1683 from the old-style calendar, and February 1684 from the new-style.

Use Numbers for Months, Not Names
If you studied Latin in high school, you’ll recognize that SEPTember means 7th month, not 9th. And OCTober is 8th, NOVember is 9th, DECember is 10th. The names of months originated in the Julian calendar, but were also used in the Gregorian calendar.

Quakers followed the English practice, with one exception. They objected to using those names of days (Sunday to Saturday) and months (January to August) which derived from pagan gods, substituting numbers. Thus Sunday was for them “First Day.” After 1752 all months were referred to by Quakers by their number. September became “Ninth Month” and so on.
The Quaker Calendar – Friends Historical Library – Swarthmore College
So the Quakers used numbers, rather than names of days and months.

Thus, Elizabeth’s survey date could be written as the 4th of the 12th month 1683, or even 4th the 12th month 1683/4.
1752 Switch to Gregorian Calendar
In 1752 England and its colonies switched from the “old-style” Julian calendar to the “new style” Gregorian calendar, which we use today.

Conclusion
Using our modern calendar, Elizabeth’s survey was done February 4, 1684.

See, once you understand it, it’s still confusing.
Nibbles Extra Credit
There’s one more date convention that’s interesting. It’s that of designating the year based on the year of the reign of the English sovereign.
For example, “9 Hen. VIII” indicates the ninth year of the reign of King Henry VIII (1509-1547). So “9 Hen. VIII” is the year 1518.
Here are some examples:


This “regnal year” was also commonly used on legal documents and declarations. Here’s an example on a land deed for Joseph Jervis in 1710.

Anne was Queen of England, Scotland and Ireland between 8 March 1702 and 1 May 1707. On 1 May 1707, under the Acts of Union, the kingdoms of England and Scotland united as a single sovereign state known as Great Britain. She continued to reign as Queen of Great Britain and Ireland until her death in 1714.
https://en.wikipedia.org/wiki/Anne,_Queen_of_Great_Britain
Sources
- Elizabeth Jarvis survey – 1684 – Pennsylvania Archives – Book A26 – Page 172
- Image of Gregorian Calendar Adoption Dates – earlychurchhistory.org
- Julius Caesar image – @bigstockphoto
- Double dating clipart – Getty Images/iStockphoto
- 7th month (September) – Pennsylvania’s 1683 Ships and Some of Their Passengers – Marion Balderston
- The History of the Ancient Parish of Sandbach – J.P. Earwaker – 1890
- Collections for a History of Staffordshire – The William Salt Archaeological Society – 1914
- The Quaker Calendar minutes – Friends Historical Library – Swarthmore College – https://www.swarthmore.edu/friends-historical-library/quaker-calendar
- https://en.wikipedia.org/wiki/Anne,_Queen_of_Great_Britain